Electric plug



E. D. WHELPLEY AND W. E. WINTERS.

ELECTRIC PLUG.

APPLICATION FILED APR.15, 1918.

1 ,337,422. Patented Apr. 20, 1920.

WI 1 5 H A TTORNEYS VEJNETED s'raras PATENT "arr: n. WHELELEY Ann WILLIAM'E. wrn'rnns, on ONEIDA, new some.

ELECTRIC ELUG.

Application filed April 15 To all whom it may concern:

Be it known that we, ELI D. WHELPLEY and WILLIAM E. WINTERS, citizens of the United States, and residents of Oneida in the county of Madison and State of ew York, have invented a certain new and useful Electric Plug, of which the following is a specification.

Our invention relates to electric plugs and has for its object a plug which can be readily inserted in standard lamp sockets without turning the plug; and particularly means for expanding the outer terminal of the plug to make electrical contact with-thethreaded shell of the socket and also interlock with the threads thereof to hold the plug in position.

The invention consists in the novel features and in the combinations and constructions hereinafter set forth and claimed.

In describing this invention, reference is had to the accompanying drawings, in which like characters designate corresponding parts in all the Views.

Figure 1 is an elevation of our plug.

Fig. 2 is a sectional view, taken on line 2-2 of Fig. 1.

This plug socket comprises generally, a body of insulation, central and outer terminals carried by the body, the outer terminal being expansible and contractile and having threads, complemental to the threads of the outer shell of a socket, as a lamp socket, and means for expanding the outer terminal into and out of position to make electrical contact with the outer shell of a socket and to mesh the threads thereof with the threads of said socket.

1 desi nates the, bod of insulation which is here s own as cylin rical in -general form and having diametrically opposite recesses 2 at its upper end which open through the periphery of the bod and also grooves 2 extending from the ower ends of the recesses to the rear end of the body- 3 is a central terminal having a shank or conductor portion 3 extending downwardly throu h the body to the rear end thereof and provi ed with a binding screw 4 to which one of the service wires is connected, the terminal end of the central terminal extend ing over the central ortion of the front or upper end of the b0 y 1. The outer terminal, in this embodiment of our invention, comprises spring tongues 5 located in the recesses 2 and normally depressed within the Specification of Letters Patent.

Patented Apr. 20, 1920.

, 1918. Serial No. 228.578.

periphery of the body of the plug and having shank or conductor portions 5 extending in lengthwise grooves 2 in the body to the rear end of the body where they are connected to the yoke 6 provided with a suitable binding screw 7 for the service wire. The portions' of the spring tongues .5 in the recesses 2 are provided with segmental threads complemental to the threads of the outer shell of the lamp socket.

The means for expanding the tongues 5 of the outer terminal comprises a sliding expander or wedge 8 in the form of a rod having a tapered portion, the rod being slidable lengthwise of a central passage 9 in the body 1 and opening through the rear end of said body, and also through the inner walls or bottoms of the recesses 2. Said means further includes members as spring tongues 10 for transferring the movement of the wedge to the terminals 5, and an operating member as a push button for controlling the movement of the wedge 8, the push button extending transversely through the body 1 and the passage 9.

As here shown, the spring tongues 10 have shanks inserted between the conductor portions 5 of the tongues 5 and the body of insulation and each has its spring portion located in one of the recesses 2 and bent in thegeneral form of a V or elbow which engages at its angle with the wedge 8 andat the end of the outer arm of the V with the contiguous tongue 5.

The push button 11 as here shown, extends entirely through a passage in the body which passage intersects the passage in which the wedge slides. The ends of the push button also extend through holes in a shell 12 to be hereinafter descrlbed. The ush button is provided within the body w1th a cam surface 13 and upper and lower seats 14 and 15 at the ends of said cam surface. The lower end of the wedge 8 normally rests upon the lower seat 15, and when the push button is operated to cause the wedge 8 to expand the outer terminal, said push button is pushed inwardly to the left, Fig. 1, cansing the inclined cam surface 13 to ride under the lower end of the wedge 8 and push the same upwardly until the lower end of thewedge 8 rests upon the seat 14, the tapered surface of the wedge during this movement,-

tion, the seat 14 passes from under the lower end of the wedge 8 and the wed e rides down the cam surface 13 t the seat under the action of the spring 18.

The collar 12 is of insulation and encircles the intermediate part of the body and terminals carried thereby, and the rear end of the body is inclosed by a cap threading on the shell 12, the cap having an opening 21 for the service wires which are connected within the cap of the binding screws 4 and! of the terminals 3 and 5.

' In operation, the plug is attached to the service wires which supply a current to various electrical appliances, as flat-irons, electric heaters, vacuum cleaners, etc., and when it is desired to connect the plug to the lamp socket, it is merely inserted 1n the socket and the pushbutton operated to expand the outer terminals 5 into engagement with the threaded outer shell of the lamp socket so that the circuit is completed from the lamp socket through the shell, and the plug is locked in the socket.-

This plug is particularly advantageous in that it can be applied to standard lamp sockets without first applying special plugs or inserts to the lamp sockets.

What we claim is:

1. An electric plug comprising a body of insulation, central and outer terminals, the outer terminal being expansible and contractile radially relatively to the body, and

means for expanding the outer terminal including a member movable lengthwise of the body, and an operating member extendingtransversely of the body and coacting with the former member, substantially as and for the urpose specified.

2. In an e ectric plug, a body of insulation, central and outer terminals carried by the body, the outer terminal being expansible and means for expanding the same in cluding a wedge movable lengthwise of the body, a member for transferring the movement of the wedge to the outer terminal, and a push button extending transversely through the body and coacting with the wedge to control the movement thereof in opposite directions, substantially as and for the purpose described.

3. In an electric plug, a body of insulation, central and outer terminals carried b the body, the outer-terminal being expansible and contractile, means for ex anding the outer terminal comprising a we ge movable lengthwise of the body, spring arms carried by the body and interposed between the wedge and the outer terminal and serving totransmit the movement of the wedge to recesses, and a transverse passage intersecting the former passage, central and outer terminals, the outer terminals including conductors extending lengthwise of the body and having spring tongue portions located in the recesses, a wedge movable lengthwise of the central passage, members extending lengthwise of the body and having V shaped portions located in the recesses, the angles of the V shaped members coacting with the wedge and the ends of the outer arms of said V members engaging thespring tongues of the outer terminal and an operating member extending into the transverse passage and coacting with the wedge, substantially as and for the purpose described.

5. In an electric plug, a body of insulation having a lengthwise passage terminating short of the outer end of the body, central and'outer terminals mounted on the body of insulation, the outer terminal being expansible and contractile, a wedge extending lengthwise of the body for expanding and permitting contraction of the outer terminal, means for moving the wedge lengthwise of the body in one direction, and a spring inserted between the end of the wedge and the other end of said passage for mov ng the wedge in the other direction, substantially as and for the purpose described.

6. In an electric plug, a body of insulation, central and outer terminals mounted on the body of insulation andhaving wire terminals at the inner ends of said body, a shell of insulation surrounding the intermediate portion of the body and the portions of the terminals thereon,'a cap threading on the rear" end of said shell and inclosing the rear end of the body and the being expansible and contractile, a wedge extending lengthwise of the body, means for transferring motion of the wedge to the outer terminal, and a push button extending transversely through the body and the shell and having "means coacting with the wedge to control the operation of the same,

substantially as and for the purpose speci- In testimony whereof we have hereunto si ed our names at Oneida, in the county of Madison, and State of New York, this 5th day of March, 1918.

ELI D. WHELPLEY. WILLIAM 'E. WINTERS. 

